Envelope machine



INVENTOR s Sheets-Sheet 1 R. COHN ENVELOPE MACHINE faker-Z M/ mwM/fi gf j 7 ATTORNEYS May 2, 1967 Filed Sept.

R. COHN ENVELOPE MACHINE May 2, 1967 3 Sheets-Sheet 2 Filed Sept. 17 1964 INVENTOR ATTORNEYS May 2, 1967 R. COHN 3,316,819

ENVELOPE MACHINE Filed Sept. 17, 1964 3 Sheets-$het 3 INVENTOR lax MM mj wf ATTORNE Y5 United States Patent 3,316,819 ENVELOPE MACHINE Robert Cohn, Millbrae, Calif assignor to Champion Paper Inc., Hamilton, Ohio, a corporation of Ohio Filed fiept. 17, 1964, Ser. No. 397,106 26 Claims. (Cl. 9362) This invention is concerned with the manufacture of folded products such as envelopes, file folders, etc. More particularly, the invention is concerned with folding and gluing apparatus for handling flat blanks of any suitable material, i.e. paper, foil, plastics, laminates, and converting same from the usual flat blank form into the folded form, One use of the invention, among others, is in conjunction With envelope machines.

This invention is concerned with folding machines. In particular the invention is concerned with an apparatus for folding fiat blanks of any suitable material, paper, foil, plastic and laminates of various types into one of a variety of products such as file folders, envelo es, etc., in completed form, or which may be used as an intermediate apparatus in a processing line for flat blanks wherein subsequent operations are performed on the folded blank to complete a given product.

The basic invention has particular utility in an envelope manufacturing operation. For this reason it will be described subsequently in terms of its incorporation into an envelope folding machine though it is to be explicitly understood that the utility of the apparatus is not so limited; the description being :used as a matter of convenience.

The use of automated machinery for performing the function of folding individual blanks cut to proper size and shape is well known and need not be belabored in any great length as to structural detail or operating components. Such patents as Welsh 2,746,364, Winkler et al. 2,132,227 among other patents disclose such machines as applied to envelope manufacture. Such automated machines, however, as are presently in use are subject to certain deficiencies including slow operative speeds; restrictions as to the type of product made and are usually highly complicated mechanisms subject to limited durability and easily maladjusted. At least some of these deficiencies result from the use of reciprocating mechanisms with high inertia factors; complicated cams subject to considerable wear; or, if the apparatus employs all rotary elements, as in the case of Novick 3,116,668, extensive manipulation of the blank is required to complete the folding process.

The present invention then, is directed to folding machines and is primarily concerned with the problem of folding and, where apropos, adhering a folded portion of a blank relative to a base and in providing as nearly as possible a rotary straight through mechanism wherein the desired result is obtained with a minimum of blank manipulation and a maximum of speed, and to a machine so constructed as to reduce to a minimum the need for excessive down time for either repairs or adjustment. Additionally, the apparatus herein described may be applied to existing equipment or incorporated in a desired machine as an integral part of its initial construction.

It is, therefore, an object of the invention to provide a rotary bottom flap gumming and sealing apparatus for general utility.

Another object of the invention is to produce a straight through flap folding mechanism.

A further object of the invention is to provide a f0lding and gluing mechanism in which the blank is positively controlled during the folding operation.

An additional object of the invention is to provide a relatively simple, maintenance free folding apparatus.

Still another object of the invention is to provide a flap folding apparatus which will produce flat fiolds or the so-called puff folds in a variety of products including envelopes.

A further object of the invention is to produce a rotary flap folder for envelopes which is adaptable to existing or in newly manufactured equipment.

An additional object of the invention is to produce a rotary machine for folding envelopes,

Still a further object of the invention is to produce a flap folding and sealing apparatus of general utility.

An additional object of the invention is to produce a rotary folding and sealing apparatus which may be advantageously used in an envelope manufacturing operation.

These and additional objects of the invention, not specifically referred to herein, but inherent in the apparatus are accomplished by providing an apparatus comprised of a blank guide on a support, a roller associated with said guide means engaging the blank, means carried by the roller for holding the blank thereon, further means carried by said roller for acting on the blank for displacing a portion thereof from the plane of the blank and an additional roller means cooperating with said first mentioned roller means to back fold said displaced portion of the blank in overlying position with respect to the remainder of the blank.

Advantageously the apparatus may include means for applying adhesive to the blank in contact with the roller and wherein said additional roller serves to adhere the back folded portion of the blank to the remainder thereof as in an envelope back flap folding operation or the like.

Having described the objects and the structure of the invention in general, consideration will now be given to details thereof in conjunction with the drawings illustrating the invention incorporated in an envelope folding apparatus, wherein- FIG. 1 is a top plan view, certain parts removed, showing the general organization of the flap folding and gumming elements,

FIG. 2 is a side schematic elevational view, somewhat enlarged, showing in detail a portion of the apparatus shown in FIG. 1, and including further the adhesive supply rolls when used and not shown in FIG. 1,

FIG. 3 is an enlarged sectional view of the folding and feed rollers showing details of these rollers,

FIG. 4 is a plan sectional view of the .folding roller shown in FIG. 3,

FIG. 5 is a view illustrating the manner in which an envelope blank is acted upon,

FIG. 6 is an illustration of one form of valve control,

FIG. 7 is an illustration of a second form of valving arrangement,

FIG. 8 is a schematic illustration of one form of drive arrangement, and

FIG. 9 is an illustration of a further form arrangement.

In describing the apparatus in detail hereinafter it should be recognized that various types of blanks, folders, envelopes and other products can be folded thereon, but for the sake of convenience its operation will be with reference to the usual type of business envelope shown in FIG. 5, since this operation illustrates not only the general utility of the invention but also is advantageous use with other devices such as adhesive appliers, side flap folders, etc. As is known, such envelopes as used for descriptive purposes herein may be folded from precut, and at times pre-scored, blanks which include a front panel F, side flaps S, a bottom flap B and top flap T. At least one folding sequence commonly used is first the folding in of said flaps S over the front panel F, the application of glue strips G to the outside of the side of valving flaps S, followed by folding of the bottom flap B over the flaps S to which it is adhered by the glue strips G. This sequence may vary, i.e. the side flaps may be folded last in which case the gumming application would be varied accordingly.

Thus considering FIG. 1 it will be seen that envelopes will be passed from left to right through the apparatus which will now be described in detail.

The frame 1 may 'be of any conventional form and is provided with conveyors 2 also of any conventional form, which move blanks of a configuration desired from a source of supply through the folding operation.

Since the envelope ablanks are conveyed, as illustrated in FIG. 5, i.e., with bottom flap B leading, as the blanks move on the conveyor 2, the side flaps S will be engaged by a pair of side flap folding plows 4 and 6 which begin the folding operation. Plows 4 and 6 cooperate with a pair of hold down elements 8 and 12, the latter holding the extreme side edges of the front panel F flat as the plows 4 and 6 fold the flaps S upwardly and finally down against the inside or back of the front panel F as shown in FIG. 5. A further press roll 14 holds the midpoint of the front panel F down to prevent its buckling due to the lateral pressure exerted thereon by the action of the plows 4 and 6.

As thus far described the following operation is purely conventional, hence the specified elements of the apparatus are shown rather broadly in FIG. 1.

As the semi-folded blanks exit from the folding plows 4 and 6, the bottom flap B has already been engaged by feed rollers 16 and 18 which, along with cooperating bottom feed rollers 22 (only one shown in FIG. 2), feed the leading edge of forward Or bottom flap B between a top guide 24 and bed plate 26 toward the folding and backing roll 28. As shown in FIG. 2, the top guide 24 of which there may be more than one, extends into the lateral space between feed rollers 16 and 18 and curves upwardly in an are extending over the surface of the folding and back-up roll 28 forming with it and bed plate 26 an arcuate guide for the forward edge of the blank. Thus, the blank is under position control as it begins its movement through the folding operation.

Disposed above the folding and backup roll 28, which latter member will be described in detail hereinafter, is an adhesive applicator, in this case a pair of applicators 32 and 34 carried by and fixed to a shaft 36 journaled in brackets 38, 42, respectively, carried on the frame 1.

As seen in FIGS. 1 and 2 the adhesive applicators 32 and 34 are rotated with shaft 36 and when they pass through that point of their rotary movement wherein they are in cooperative relation with folding and backup roll 28, these applicators are positioned in a converging angular relationship. This relationship is such that the applicators contact the folded side flaps S to apply adhesive thereto in the form of strips G (FIG. Thus in the particular environment shown the applicators may rotate one revolution per item passed through the apparatus and their rotary speed is coordinated with the rotary speed of folding roller 23. Of course the number, shape and position of the adhesive applicators may vary considerably or some may be dispensed with entirely, depending on the item being folded. Thus, it is to be understood that same are described as applied to the exemplary descriptive matter and to the product used in the example.

As shown in FIG. 2, the adhesive to be applied by applicators is supplied to a pan 38 by any suitable means and is picked up therefrom by a pickup roller 42 which is in engagement with a transfer roller 44. The latter roller, disposed above the adhesive applicators 32, 34 is so positioned that, as the applicators are rotated, their cylindrical surfaces contact the transfer roll 44 to carry adhesive therefrom to the point of transfer of the adhesive to the proper position on the material being acted upon, in this case the back of side flaps S of the envelope. It will, of course, be noted that the folding and backup roll 28 and the adhesive applicators 32, 34 rotate in opposite directions, roll 28 rotating clockwise; applicators 32, 34 counter clockwise, as illustrated by the arrows in FIG. 2.

Digressing, at this point, from the overall operation of the apparatus, attention is directed to FIGS. 3 and 4 which show in detail the construction of the folding and backup cylinder 28. As seen in FIG. 3, this cylinder is hollow being comprised of an outer shell 44 provided throughout at least one portion of its surface with a perforated area defined by apertures 46, and also with a transverse slot 48. Also formed in conjunction with slot 48 is a circumferentially and transversely extending depressed area 52 into which is offered by suitable countersunk bolts 54, contact cement or other fastening means an arcuate contact plate 56 formed of a material suitable for the product being processed, such as rubber, aluminum, or combinations thereof suitably fastened in depressed area 52.

The hollow shell 44 is in turn, closed with end caps 58 and 62 fixed by suitable connectors 64 to the ends thereof and in turn carried on shaft 66 to which they in turn are fixed by flanged couplings 68, 72 or other fastening means. Thus shaft 66 and shell 44 are rotatable as a unit, the shaft 66 being journaled for rotation in suitable bearing blocks, not shown, mounted on frame 1.

As was set forth above, the cylindrical shell 44 is provided with a slot 48. Into this slot there is inserted and fixed by cap screws 74 a vacuum bar 76. This bar is provided with an interior chamber 78 closed at its ends by end caps 58, 62, which chamber opens to the exterior surface 62 of the vacuum bar 76 via a transverse suction slot 84. It will be noted that slot 84 does not open radially to the exterior surface of the bar, but is disposed tangentially of the chamber 78.

As shown in FIG. 4, the interior of the hollow cylinder 44 is pressurized such that air pressure is communicated to ports 46. This is accomplished by providing shaft 66, at one end with an interior port 86 which opens at 88 to the interior of the roll 28. The port 86 also opens at its opposite end, exteriorly of the end cap 62, and this opening 92 is in communication with a slip-ring type of connector 94 with any conventional source of air pressure in a manner to be described.

The vacuum bar 76 is in communuication with any suitable vacuum pump by means of an L-shaped port 96 formed in end cap 58, covered by the flanged connector 68. This port 96 communicates with a shaft port 98 which, like port 86, has its ends opening outwardly from the shaft, respectively, interiorly of and exteriorly of the end cap 58. A suitable and conventional slipring connector 102 is in communication with shaft port 98 and the vacuum pump, thus a vacuum may be drawn through vacuum bar chamber 78 and port 84.

Considering again FIGS. 2 and 3, it will be seen that the folding and backup roll 28, described above, also cooperates with one or more, in this case a pair of rolls 104, 104' carried on shaft 106 which is also suitably mounted in journals on frame 1. These rolls 104, 104 referred to as folding and. feed rolls hereinafter, rotate counter clockwise and with the roll 28 define a nip. Rolls 104, 104' are provided with a suitable cover 108, 103, usually resilient, fabricated of a fir-mly resilient material similar to that used for contact plate 54. In addition, the covers 108, 108 may be interrupted at 112 as are the cylindrical surfaces of rolls 104, 104' to form a transverse flattened area which, in turn will, periodically cause discontinuance of the nip defined between the surfaces of the roll 28 and themselves. The purpose of this arrangement which is optional will become apparent hereinafter. It will be noted here that rolls 104, 104 are driven so that their surface speed is idintical with the surface speed of the folding and backup r0 28.

Considering now FIG. 2 in conjunction with FIG. 3, in particular, and the descriptive material relating thereto, it will be seen that as an envelope blank passes over bed plate 26, and beneath guide 24, it is brought into contact with the surface of the roll 28. If then, as is the case, the

surface speed of roll 28 is so coordinated with the linear speed of a blank entering between itself and guide 24, as to bring the vacuum bar into contact with the blank at a juncture line J-J (FIG. 5), formed at the place of the fold between flap B and front panel F, it will be seen that the front panel F will become firmly anchored to the roll 28 while the leading edge of the blank and that portion thereof from the edge back to the juncture line J-I, namely back flap B, will be free. If, as soon as the blank is fixed to cylinder 28 by suction through ports 84, pressure is admitted to the interior of cylinder 28 and hence out through ports 46, it will be seen that the free portion of the blank, namely flap B, will then be blown upward away from the folding and backup roll 28 against the upwardly curved end of guide 24, generally at a right angle with respect to panel F. At this point the blank passes into the nip formed between roll 28 and rolls 104, 104 at the juncture line J--] and the flap B is thus folded and pressed down against the front panel F and the previously folded side flaps S. Since the glued strips G have been previously applied by applicators 32, 34 to the flaps S the back panel B is thus caused to adhere to these side flaps and the pressure created by the folding action 56 and coverings 108, 108' of rollers 104, 104' will be sufficient to bring about such adherence.

As the now folded blank and the suction bar 74 approach an angular position approaching exit bed plate 114, the vacuum is cut oif with the result that the envelope travels over bed plate 114 and is picked up by exit feed rollers116, 118 (FIG. 2) and conveyed from the folding mechanism for further and conventional processing as is customary in the art.

As previously pointed out each of the rollers 104, 104 may be provided with a discontinuous cylindrical surface as illustrated in FIG. 3 and defined by a transverse recess 112. This form of folding and feed roll is used with particular advantage where a so-called puff type envelope is to be folded because initial contact between the cylindrical surfaces 103 and 54 can be timed to occur at a point after the fold point has progressed between the two rolls 104, 104' and backup roll 28. Thus the juncture or nip line I---] may be moved rearwardly relative to the fold line defined between front panel F and back panel B as indicated by the dotted line J of FIG. 5 so that the fold line is not creased or compressed at thi point. Sincepress rolls 104, 104 are disposed inwardly of the ends of the envelope and do not engage same at the fold line between side flaps S and panel F this fold line is also rolled" rather than a sharply defined crease and a socalled puff" envelope is formed. Where, of course, the usual sharply folded envelope is desired rolls 104, 104 may be utilized without the discontinuous surface and, more often than not, they can be replaced with a single wide roll to compress the whole envelope against the contact surface 54 of roll 28, thus sharply creasing the fold lines between panel F, flaps S and back panel B. The apparatus then is capable of producing a variety of fold styles or types of folded articles with a minimum of change or modification.

Various types of means may be utilized to affect the application of vacuum and fluid pressure to roll 28. For example, FIGS. 6a and 6b illustrate an arrangement Wherein slip rings 94 and 102 respectively, in conjunction with shaft 66, act as rotary valves. In such an arrangement, port 92 in shaft 66 is in communication with slip ring 94 by means of a fitting 122 which in turn communicates with an arcuate chamber 124 such that pressure is established between port 86 and the source only while chamber 124 is in rotary alignment with fitting 122. Similarly, vacuum is controlled through shaft 66. to vacuum bar 76 via fitting 128, arcuate chamber 132 and radially extending port 134 in shaft 66, and a vent port 133. The position of and the arcuate extent of chambers 124 and 132 determines the extent of rotary travel in which air and vacuum are applied to roll 28 and as may be seen from these figures, the vacuum is applied considerably earlier than air pressure and remains on for a brief period after air pressure is cut off to obtain the hold down and folding function as has been previously described in the folding of the illustrative product.

FIGS. 7a and 7b show a variation in the arrangement wherein slip rings 94' and 162' are provided with internal annular ports 142 and 144 respectively and diametric ports 146, 143 are provided in shaft 66 at its respective ends. The sources of air pressure and vacuum are in communication with annular ports 142, 144 via valves 150, 1611, the former venting to atmosphere, which are in turn controlled by cams 151 and 161 respectively. The cams in turn may be driven at the same speed as shaft 66 from any suitable point in the drive mechanism for 200 by any one of a number of conventional gearing or chain and sprocket arrangements. Preferably, however, for convenience, bot-h cams 151, 161 would be mounted on a common shaft 260 directly driven from shaft 66 to preclude misalignment between the position of cylinder 28 and the turn on-turn off of the air pressure and/or vacuum and to reduce to a minimum the usual backlash inherent in any mechanically geared system.

In FIG. 9 there is disclosed a further folding and hold down roll structure which incorporates a self-contained valving arrangement. As shown in this figure of the drawing the shell 156 of cylinder 23 is formed as a closed cylinder having planar end walls 158, 162. Suction bar 76 is positioned, as before in slot 48 in the cylindrical wall and is provided with port 173 which opens at the vacuum end thereof. The cylinder is also provided with perforations 46 positioned in the shell 156 relative to the slot 48 as previously described. Also, the end wall 162 is provided with a port 164 which places the hollow interior of the cylinder with the exterior of the wall 162.

In abutting relationship with end walls 158 and 162 are two disc-like members 166 and 168 which define wear plates and may be formed of any suitable wear resistant material, of which nylon is an example. These wear plates 166, 168 are suitably fixed to the end walls 153, 162 as by bolts 170 and are provided with openings 172,

.174 respectively aligned with ports 173 in vacuum bar 76 and port 164 in end wall 162 respectively. That is to say, wear plate port 172 aligns with port 176 at one side of the cylinder while port 174 in wear plate 168 aligns with port 164 in the end wall of cylinder 156.

Concentric with the cylinder 26 and mounted on shaft 66 therewith and along with wear plates 166, 166 are valve plates 178, 182. These valve plates are provided with central bushings 184, 186 so that if held stationary as they are in fact, the shaft 66 may rotate freely therein, while both wear plates 166 and 168 and cylinder 28 may be rotated with shaft 66 and hence relative thereto. Valve plate 173 is provided with an arcuate port 166 and vent hole 189, while valve plate 182 is provided with arcuate port 191 and a vent port 191. Both arcuate ports 188 and 1911 open in their entirety against the wear plates 166 and 168 and constitute therewith rotary valves 'iwhereby the admission of pressure to the interior of cylinder 156 and hence to ports 46 and of vacuum to vacuum bar 76 may be readily controlled as the cylinder rotates with shaft 66 and relative to these valve plates. Obviously, the ports 13$, 1% may be of such an arcuate length as to provide suitable admission time for both pressure and vacuum provided through connectionsP and V respectively.

Thus it may be seen that as cylinder 28 rotates the ports 188, 191 will be placed in communication with ports 46 and 78 so as to periodically apply pressure and vacuum to these ports respectively at a given place and for a given period of arcuate movement of the roller at 7 each revolution thereof. While not shown, it is believed equally obvious that if the valve plates 178 and 182 are adjustably held from rotation with respect to cylinder 28, that the period of vacuum and pressure application and cutoff can readily be varied relative to the rotary position of the cylinder in any given revolution so that, as will be explained, the apparatus can accommodate various lengths of material to be folded. Too, this arrangement will enable minute adjustments of the apparatus to assure proper functioning over long periods of time for any given product.

As has been stated under the circumstances of use of the descriptive example, the vacuum is applied to the blank prior to pressure. Where, however, that portion of the blank to be folded is quite long, as for example a :file folder, relative to the unfolded portion of the blank, it may prove desirable to reverse the procedure. In other words, to move a long flap against guide 24 before the vacuum bar engages the fold point and the unfolded base its fixed by suction to the cylinder 28.

Thus it may be seen that the apparatus can be accommodated to the manufacture of various folded products easily and efficiently.

Turning now to FIG. 8, there is outlined in schematic :form a drive mechanism for the apparatus in question.

Motor M supplies power to a variable speed trans- .mission V. The output shaft 201 of the transmission is connected via sprocket 203 and chain 205 to a drive sprocket 2137. Sprocket 207 drives shaft 209 which is connected via a rotary registration device R to sprocket 211. Sprocket 211 via chain 213 and sprocket 215 drives the folding backup roll 28. Sprocket 215 through gears 217, 219, which reverse the direction of rotation imparted, drive to shaft 36 which carries the adhesive applicators 32 and 34 and also, via gears 223 and 225, the folding and feeding rolls 104, 104'. Thus any adjustment of the angular position of the folding and gumming cylinder 28 with respect to the point at which an envelope blank engages same will also result in adjustment of the adhesive applicators and folding and feeding rolls 104, 104 concurrently. Thus, for example the entire folding and gumming operation can be varied to compensate for differences in flap length where different size blanks or material is folded on the same apparatus. The adjustment is provided for by any conventional form of rotary registration device which provides for relative angular adjustment between a shaft and a gear or two shafts, such devices being well known in the printing art among others.

Shaft 201 also drives sprocket and chain or gear drives 227, 229, 231, 233, the lower feed rolls 22 and 116, and also via gears 235, 237, and chains and sprockets 239, 241, 243, 245, the upper feed rolls 16 and 114.

It will be appreciated that the drive arrangement shown is but one form by which the drive may be affected, since, obviously, a completely geared system would be equally effective. T00, the type of drive used may, in part, be dictated by the existing structure where the present apparatus is applied to existing machines.

As has been mentioned, the invention can be supplied in kit form for adapting existing equipment to rotary operation. For example, by merely substituting the folding and gumming roll 28 and the folding and feed rolls 104, 104, and providing a suitable drive, a conventional tucker and roll machine may be readily converted to rotary operation.

Having described the invention, it will be obvious that various changes and modifications will occur to those skilled in the art and it is to be understood that such modifications and changes fall within the spirit and scope of the invention which is limited only as defined in the following claims.

What is claimed is:

1, In an envelope folding machine including means for feeding a blank and means for folding the side flaps thereof into overlying relation with respect to the front panel of said blank, and means for applying adhesive strips to the back of said folded side flaps, the improvement comprising rotary means for folding the back panel of said blank into adherent relation overlapping said side flaps, said means including a rotary folding and backup roller having means for positioning and holding the blank during folding of said back flap, means carried by said roller for displacing the flap from the plane of the front panel while the blank is positioned on the roller and nip defining means engaging the blank while positioned on said roller to compressively adhere said back flap to said side flaps.

2. The apparatus as defined in claim 1, wherein said means for positioning and holding said blank during folding comprises a vacuum bar carried by said folding and backup roller.

3. The apparatus of claim 1, wherein said flap displacing means comprises a series of air pressure ports provided in the surface of said roller.

4. The apparatus of claim .1 wherein said nip defining means comprises a further roll in contact with said folding and backup roll.

5. The apparatus of claim 4 wherein the surface of said further roll is discontinuous.

6. The apparatus of claim 5 including means to drive said backup roll and said further roll in synchronism.

7. An envelope folding machine for blanks having a front panel, side flaps foldable over the back of the front panel and a back flap adhered to the back of the side flaps comprising a blank feeding means, means for folding said side flaps, a blank guide means, a roller associated with said blank guide means, means adjacent to and contacting a blank on said roller for applying adhesive to the backs of said folded side flaps, said roller including means to hold a blank thereon, and means for folding the back flap into adherent contact with the adhesive coated side flaps.

8. The combination of claim 7 wherein said folding means comprises a source of air pressure and means carried by said roll for exhausting said air against the back flap and means engaging said fiap and in contact with said roller to fold and adhere said flap to said side flaps.

9. The combination of claim 7 wherein said means for holding said blank on said rol-ler comprises a vacuum source on said roller.

10. The combination of claim 7 including automatic valve means for controlling the exhaust of air pressure against said back flap.

1 1.'The combination of claim 7 wherein said valve means comprises a rotary valve.

12. The combination of claim 9 including automatic valve meanscontrolling said vacuum source.

16. A roller for rotary envelope machines comprising a hollow cylinder, a slot in said cylinder, a ported bar in said slot, a series of perforations in the surface of said cylinder adjacent said slot, means closing the ends of the cylinder and port means for connecting air pressure to the interior of said cylinder and a vacuum source to said ported bar.

'14. A roller as defined in claim 13 including further a shaft supporting said closing means and port means in said shaft in communication with a vacuum source and a pressure source respectively, valve means carried by said shaft for connecting said sources to the interior of said cylinder and to said ported bar independently of one another.

15. An envelope folding apparatus comprising a blank guide, a roller associated with said blank guide and engaging a blank, means associated with said roller to apply adhesive to selected portions of said blank when in contact with said roller, means carried by said roller for holding the blank thereon and further means carried by said roller acting on a blank to fold a portion thereof ba k P0 1 itself and further roller means acting with 9 said first mentioned roller to adhere said back folded portion of the blank to the adhesive coated areas thereof.

16. The combination defined in claim 15, wherein said further roller means is provided with a discontinuous cylindrical surface which engages the back folded portion of the blank at a line spaced behind the folded back portion thereof and the remaining portion of said blank.

17. A folding machine comprising rotary means for folding a portion of a blank into overlapping relation with respect to another portion thereof, said means including a rotary folding and backup roller having means for positioning and holding the blank during folding of said first portion, means carried by said roller for displacing the first portion of the blank from the plane of the second portion thereof while the blank is positioned on the roller and nip defining means engaging the blank while positioned on said roller to complete the folding operation.

18. The apparatus as defined in claim 17, wherein said means for positioning and holding said blank during folding comprises a vacuum bar carried by said folding and backup roller.

.19. The apparatus of claim 17, wherein said flap displacing means comprises a series of air pressure ports provided in the surface of said roller.

20. The apparatus of claim 17, wherein said nip defining means comprises a further roll in contact with said folding and backup roll.

21. The apparatus of claim 20, wherein the surface of said further roll is discontinuous.

22. The apparatus of claim 21 including means to drive said backup roll and said further roll in synchronism.

23. A roller for rotary folding machines comprising a hollow cylinder, a slot in said cylinder, a ported bar in said slot, a series of perforations in the surface of said cylinder adjacent said slot, means closing the ends of the cylinder and ort means for connecting air pressure to the interior of said cylinder and a vacuum source to said ported bar.

24. A roller as defined in claim 23 including, further, a shaft supporting said closing means and port means in said shaft in communication with a vacuum source and a pressure source respectively, valve means carried by said shaft for connecting said sources to the interior of said cylinder and to said ported bar independently of one another.

25. A folding apparatus comprising a blank guide, a roller associated with said blank guide .and engaging a blank, means associated with said roller to apply adhesive to selected portions of said blank when in contact with said roller, means carried by said roller for holding the blank thereon and further means carried by said roller acting on a blank to fold a portion thereof back upon itself and further roller means acting with said first mentioned roller to adhere said back folded portion of the blank to the adhesive coated areas thereof.

25. The combination in claim 25, wherein said further roller means is provided with a discontinuous cylindrical surface which engages the back folded portion of the blank at a line spaced behind the folded back portion thereof and the remaining portion of said blank.

References Cited by the Examiner UNITED STATES PATENTS 2,202,496 5/ 1940 La Bombard 93-6:1 X 3,079,847 3/1963 Polidori 93-62 3,088,382 5/1963 Winkler et al. 93-62 3,116,668 1/1964 Novick 93-62 BERNARD STICKNEY, Primary Examiner. 

1. IN AN ENVELOPE FOLDING MACHINE INCLUDING MEANS FOR FEEDING A BLANK AND MEANS FOR FOLDING THE SIDE FLAPS THEREOF INTO OVERLYING RELATION WITH RESPECT TO THE FRONT PANEL OF SAID BLANK, AND MEANS FOR APPLYING ADHESIVE STRIPS TO THE BACK OF SAID FOLDED SIDE FLAPS, THE IMPROVEMENT COMPRISING ROTARY MEANS FOR FOLDING THE BACK PANEL OF SAID BLANK INTO ADHERENT RELATION OVERLAPPING SAID SIDE FLAPS, SAID MEANS INCLUDING A ROTARY FOLDING AND BACKUP ROLLER HAVING MEANS FOR POSITIONING AND HOLDING THE BLANK DURING FOLDING OF SAID BACK FLAP, MEANS CARRIED BY SAID ROLLER FOR DISPLACING THE FLAP FROM THE PLANE OF THE FRONT PANEL WHILE THE BLANK IS POSITIONED ON THE ROLLER AND NIP DEFINING MEANS ENGAGING THE BLANK WHILE POSITIONED ON SAID ROLLER TO COMPRESSIVELY ADHERE SAID BACK FLAP TO SAID SIDE FLAPS. 